How many yards of fabric to buy for 42 inch square of fabric?

To make a 42-inch square from fabric, you would need at least 1.5 yards of fabric. This is because 1 yard equals 36 inches, so you need a bit more than 1 yard to cover both dimensions of the square. When buying fabric, it's often wise to purchase a little extra to account for seams and any potential errors. Therefore, 1.5 yards is a practical amount to ensure you have enough.